This is a 46 slide powerpoint reviewing a unit about plant cells and animal cells and their organelles, the organization of living things: cells-tissues-organs-organ systems-organisms, and the human body systems. (7th-grade science essential standards). It is best used with the "Organization of Living Things Review Guide" and the "Organization of Living Things Unit Test" I use the powerpoint for student whiteboard races, which students find exciting and engaging. Each powerpoint slide posts a question or vocabulary word definition - and students race write the correct word or answer their whiteboards. It could be used for different review games depending on the class and resources.